mmc_block: add support for secure discard

Secure discard is implemented by Secure Trim if the discard is unaligned
or Secure Erase otherwise.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Gardiner <bengardiner@nanometrics.ca>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 03f96e9..d545f79 100644 (file)
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -280,6 +280,42 @@ out:
        return err ? 0 : 1;
 }
 
+static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
+                                      struct request *req)
+{
+       struct mmc_blk_data *md = mq->data;
+       struct mmc_card *card = md->queue.card;
+       unsigned int from, nr, arg;
+       int err = 0;
+
+       mmc_claim_host(card->host);
+
+       if (!mmc_can_secure_erase_trim(card)) {
+               err = -EOPNOTSUPP;
+               goto out;
+       }
+
+       from = blk_rq_pos(req);
+       nr = blk_rq_sectors(req);
+
+       if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
+               arg = MMC_SECURE_TRIM1_ARG;
+       else
+               arg = MMC_SECURE_ERASE_ARG;
+
+       err = mmc_erase(card, from, nr, arg);
+       if (!err && arg == MMC_SECURE_TRIM1_ARG)
+               err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
+out:
+       spin_lock_irq(&md->lock);
+       __blk_end_request(req, err, blk_rq_bytes(req));
+       spin_unlock_irq(&md->lock);
+
+       mmc_release_host(card->host);
+
+       return err ? 0 : 1;
+}
+
 static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
 {
        struct mmc_blk_data *md = mq->data;
@@ -510,10 +546,14 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
 
 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 {
-       if (req->cmd_flags & REQ_DISCARD)
-               return mmc_blk_issue_discard_rq(mq, req);
-       else
+       if (req->cmd_flags & REQ_DISCARD) {
+               if (req->cmd_flags & REQ_SECURE)
+                       return mmc_blk_issue_secdiscard_rq(mq, req);
+               else
+                       return mmc_blk_issue_discard_rq(mq, req);
+       } else {
                return mmc_blk_issue_rw_rq(mq, req);
+       }
 }
 
 static inline int mmc_blk_readonly(struct mmc_card *card)

diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 3b15884..e876678 100644 (file)
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -141,6 +141,9 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
                        mq->queue->limits.discard_alignment =
                                                        card->erase_size << 9;
                }
+               if (mmc_can_secure_erase_trim(card))
+                       queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD,
+                                               mq->queue);
        }
 
 #ifdef CONFIG_MMC_BLOCK_BOUNCE